LISA-U1 series - System Integration Manual
3G.G2-HW-10002-3
Preliminary
Handling and soldering
Page 119 of 125
4.2.3
Optical inspection
After soldering the LISA-U1 series modules, inspect the modules optically to verify that he module is properly
aligned and centered.
4.2.4
Cleaning
Cleaning the soldered modules is not recommended. Residues underneath the modules cannot be easily
removed with a washing process.
Cleaning with water will lead to capillary effects where water is absorbed in the gap between the baseboard
and the module. The combination of residues of soldering flux and encapsulated water leads to short circuits
or resistor-like interconnections between neighboring pads. Water will also damage the sticker and the ink-
jet printed text.
Cleaning with alcohol or other organic solvents can result in soldering flux residues flooding into the two
housings, areas that are not accessible for post-wash inspections. The solvent will also damage the sticker
and the ink-jet printed text.
Ultrasonic cleaning will permanently damage the module, in particular the quartz oscillators.
For best results use a "no clean" soldering paste and eliminate the cleaning step after the soldering.
4.2.5
Repeated reflow soldering
Only a single reflow soldering process is encouraged for boards with a LISA-U1 series module populated on it.
The reason for this is the risk of the module falling off due to high weight in relation to the adhesive properties
of the solder.
4.2.6
Wave soldering
Boards with combined through-hole technology (THT) components and surface-mount technology (SMT) devices
require wave soldering to solder the THT components. Only a single wave soldering process is encouraged for
boards populated with LISA-U1 series modules.
4.2.7
Hand soldering
Hand soldering is not recommended.
4.2.8
Rework
The LISA-U1 series modules can be unsoldered from the baseboard using a hot air gun.
Avoid overheating the module.
After the module is removed, clean the pads before placing.
Never attempt a rework on the module itself, e.g. replacing individual components. Such
actions immediately terminate the warranty.
4.2.9
Conformal coating
Certain applications employ a conformal coating of the PCB using HumiSeal
®
or other related coating products.
These materials affect the HF properties of the LISA-U1 series modules and it is important to prevent them from
flowing into the module.
The RF shields do not provide 100% protection for the module from coating liquids with low viscosity, therefore
care is required in applying the coating.
Conformal Coating of the module will void the warranty.
